1. Field of the Invention
The present invention relates to an inspection apparatus, an inspection method, and a computer-readable storage medium.
2. Description of the Related Art
As discussed in Japanese Patent Application Laid-Open No. 2010-249565, it is conventionally known to collate a reading target image read by an imaging unit with a reference image to detect a defective portion (i.e., an image defect portion) in the reading target image. According to the above-described conventional technique, each reading target image is divided into a plurality of areas. A part of the areas of the reading target image is first subjected to a low-precision positioning processing with respect to the reference image and subsequently subjected to a high-precision positioning processing. The result of the low-precision positioning processing performed in the above-described partial area is directly used for a remaining area. Subsequently, the high-precision positioning processing is performed on the remaining area with respect to the reference image. As described above, it is feasible to reduce the amount of calculations required for the positioning processing and increase the processing speed by reflecting a low-precision positioning processing result of a partial area to high-precision positioning processing to be performed in other areas.
Although it depends on the feature (e.g., occurrence position) of an image defect, an image defect portion can be detected by performing collating after completing the low-precision positioning processing. However, according to the technique discussed in Japanese Patent Application Laid-Open No. 2010-249565, even the above-described area is subjected to the high-precision positioning processing. The high-precision positioning processing requires a great amount of calculations. Therefore, speedily completing the processing is feasible by eliminating the high-precision positioning processing when it is not necessary.